Re: [PATCH 28/62] PNP: isapnp: Check the isapnp_cfg_begin() return value

[Rafael J. Wysocki]

On Mon, Feb 23, 2026 at 11:03 PM Bart Van Assche
<bart.vanassche@xxxxxxxxx> wrote:
>
> From: Bart Van Assche <bvanassche@xxxxxxx>
>
> Instead of ignoring isapnp_cfg_begin() failures, propagate the value
> returned by this function in case of a failure. This patch prepares
> for enabling thread-safety analysis since isapnp_cfg_begin() only locks
> a particular mutex if it returns zero.
>
> Cc: Jaroslav Kysela <perex@xxxxxxxx>
> Cc: Adam Belay <ambx1@xxxxxxxxxx>
> Cc: Rafael J. Wysocki <rafael@xxxxxxxxxx>
> Cc: linux-acpi@xxxxxxxxxxxxxxx
> Fixes: f72e5c5c861c ("[PATCH] PnP Rewrite V0.9 - 2.5.43")
> Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>

Acked-by: Rafael J. Wysocki (Intel) <rafael@xxxxxxxxxx>

> ---
>  drivers/pnp/isapnp/core.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pnp/isapnp/core.c b/drivers/pnp/isapnp/core.c
> index 219f96f2aaaf..3591a2791c1a 100644
> --- a/drivers/pnp/isapnp/core.c
> +++ b/drivers/pnp/isapnp/core.c
> @@ -853,7 +853,9 @@ static int isapnp_get_resources(struct pnp_dev *dev)
>
>         pnp_dbg(&dev->dev, "get resources\n");
>         pnp_init_resources(dev);
> -       isapnp_cfg_begin(dev->card->number, dev->number);
> +       ret = isapnp_cfg_begin(dev->card->number, dev->number);
> +       if (ret)
> +               return ret;
>         dev->active = isapnp_read_byte(ISAPNP_CFG_ACTIVATE);
>         if (!dev->active)
>                 goto __end;
> @@ -887,10 +889,12 @@ static int isapnp_get_resources(struct pnp_dev *dev)
>  static int isapnp_set_resources(struct pnp_dev *dev)
>  {
>         struct resource *res;
> -       int tmp;
> +       int tmp, ret;
>
>         pnp_dbg(&dev->dev, "set resources\n");
> -       isapnp_cfg_begin(dev->card->number, dev->number);
> +       ret = isapnp_cfg_begin(dev->card->number, dev->number);
> +       if (ret)
> +               return ret;
>         dev->active = 1;
>         for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
>                 res = pnp_get_resource(dev, IORESOURCE_IO, tmp);
> @@ -936,9 +940,13 @@ static int isapnp_set_resources(struct pnp_dev *dev)
>
>  static int isapnp_disable_resources(struct pnp_dev *dev)
>  {
> +       int ret;
> +
>         if (!dev->active)
>                 return -EINVAL;
> -       isapnp_cfg_begin(dev->card->number, dev->number);
> +       ret = isapnp_cfg_begin(dev->card->number, dev->number);
> +       if (ret)
> +               return ret;
>         isapnp_deactivate(dev->number);
>         dev->active = 0;
>         isapnp_cfg_end();